Chevrolet Repair: 99 Chevy Prizm, chevy prizm, chevy prism

Question
My '99 Chevy prism had it's check engine light flashing and when I stopped the car was jerking. I checked the oil and was fine, same with the coolant. I drive this car to work and school each day and I have no idea what the problem could be. The check engine light has been on before, checkers told me it was because the ring around my gasline was rusted but it was not going to be an issue.

Answer
HI MICHELLE, THE REASON YOUR CK ENGINE LIGHT IS FLASHING IS BECAUSE YOUR ENGINE IS SKIPPING. THIS WILL MAKE THE ENG JERK AS YOU SAY..CAUSES FOR YOUR ENG TO SKIP COULD BE CAUSED BY ONE OF THE FOLLOWING,  BAD SPARK PLUG ,IGNITION WIRES, COIL, BAD FUEL INJECTORS,BURNED VALVE. WHEN THE CK ENG LIGHT WAS ON BEFORE THIS WAS A DIFFERENT CODE, YOU SAY THEY TOLD YOU A LOOSE GAS CAP PROBLEM. THIS WOULD BE A CODE FOR A EVAP FAULT. THIS WILL [HAVE NOTHING] TO DO WITH WHAT IS GOING ON NOW..THE BEST WAY TO FIND OUT WHICH CYLINDER IS CAUSING THE ENG TO SKIP IS TO TAKE IT TO YOUR LOCAL SHOP AND HAVE THEM SCAN THE COMPUTER AND HAVE THEM TELL YOU WHAT THE CODE IS.. WILL BE SOMETHIBG LIKE PO303 OR PO302.... 303 WOULD BE A SKIP ON #3 CYLINDER AND CODE# 302 IS A SKIP ON # 2 CYLINDER ,YOU GET THE IDEA.. ONCE YOU KNOW WHICH CYLINDER IS SKIPPING THEN YOU CAN REMOVE THE SPARK PLUG AND CK THAT AND THEN THE IGNITION WIRES AND SO ON..LET ME KNOW WHAT YOU COME UP WITH AND WE WILL GO ON FROM HERE. HOPE THIS HELPS YOU TO THIS POINT,,,,TOM..